Function _get_immediate_cls_attr

lib/sqlalchemy/orm/decl_base.py:179–215

return an attribute of the class that is either present directly on the class, e.g. not on a superclass, or is from a superclass but this superclass is a non-mapped mixin, that is, not a descendant of the declarative base and is also not classically mapped. This is used to detect at

(
    cls: Type[Any], attrname: str, strict: bool = False
)

def _get_immediate_cls_attr(
    cls: Type[Any], attrname: str, strict: bool = False
) -> Optional[Any]:
    """return an attribute of the class that is either present directly
    on the class, e.g. not on a superclass, or is from a superclass but
    this superclass is a non-mapped mixin, that is, not a descendant of
    the declarative base and is also not classically mapped.

    This is used to detect attributes that indicate something about
    a mapped class independently from any mapped classes that it may
    inherit from.

    """

    # the rules are different for this name than others,
    # make sure we've moved it out.  transitional
    assert attrname != "__abstract__"

    if not issubclass(cls, object):
        return None

    if attrname in cls.__dict__:
        return getattr(cls, attrname)

    for base in cls.__mro__[1:]:
        _is_classical_inherits = _dive_for_cls_manager(base) is not None

        if attrname in base.__dict__ and (
            base is cls
            or (
                (base in cls.__bases__ if strict else True)
                and not _is_classical_inherits
            )
        ):
            return getattr(base, attrname)
    else:
        return None


def _dive_for_cls_manager(cls: Type[_O]) -> Optional[ClassManager[_O]]: